This invention relates to a duct system for distributing humidified air from humidifying apparatus. More particularly, this invention relates to an eliminator sheet assembly to be mounted at an outlet of a duct system, a structural member for mounting the eliminator plate assembly, and a drain plate assembly.
Centrifugal humidifiers are often utilized to increase the humidity in textile and other industrial processing rooms. To distribute the humidified air, which also contains a quantity of water in the form of fine droplets, to different locations in such rooms, a duct system is coupled to receive this air from the humidifier. A conventional duct system includes an elongated duct admitting humidified air at one end and discharging the humidified air at outlets formed at intervals along the sides of the duct.
In addition, the duct system includes eliminator sheet assemblies mounted at the outlets to remove a limited part of the droplets entrained in the humidified air. The eliminator sheet assemblies are therefore often referred to as limited eliminators. Typically, the eliminator sheet assemblies remove all droplets above a certain size, such as 60 microns. Droplets smaller than this certain size are allowed to leave the outlets with the air in the form of a fine mist.
Further, the duct system typically includes means for capturing droplets being emitted at the outlets from the lower region of the eliminator sheet assemblies, and a drain plate assembly mounted to extend beneath the duct to catch condensation falling from the duct.
One drawback of the previous duct systems has involved directing the flow of air from the outlets in directions other than straight out, for example to one side or the other. Duct systems are normally hung to extend along ceilings; and because of obstructions, such as beams and piping, different directions of air discharge are preferred. In the past, to change the air discharge direction has required the replacement of one eliminator sheet assembly by another. The air discharge direction is normally determined by the position of the eliminator sheets mounted within the assembly; and heretofore the position of the eliminator sheets has been fixed for a particular assembly. Furthermore, the eliminator sheets of the prior art have had directional characteristics which have prevented eliminator sheet assemblies from being moved from one side to the other of a duct without the eliminator sheet being inverted.
The droplet capturing means employed at duct outlets in the prior art have typically included a pan or sheet extending outward from the side of the duct opposite an outlet. This pan or sheet served no purpose other than capturing droplets. The pan or sheet added significant weight, which is a disadvantage when hanging a duct system for a ceiling.
Previous drain plate assemblies for duct systems have had to compromise between ease of cleaning and the time interval between cleanings. The drain plate assemblies of the prior art have typically included flat-bottomed trough mounted to extend beneath the duct, with the trough having approximately the same width as the duct. The compromise centers on the closeness with which the trough is mounted to the duct. If the trough were mounted at a distance allowing cleaning in place, the accumulation of waste and dust in the trough from circulation of room air over the trough would be accelerated and the interval between cleanings would be reduced. If the trough were mounted in closer proximity to the duct, cleaning would require removal of the trough.